Oxygen concentrator for mechanical ventilation

Abstract

An oxygen concentrator is configured to provide oxygen at either lower pressures or higher pressures. When providing low pressure oxygen, the disclosed oxygen concentrator may be used with a conventional, low pressure oxygen delivery device, such as an oxygen cannula or mask, that is configured to deliver oxygen at approximate source pressures of 5 psig to 8 psig. When providing high pressure oxygen, the disclosed oxygen concentrator may be used with a high pressure oxygen delivery device, such as a low profile nasal cannula, that is configured to deliver oxygen at higher pressures. The disclosed oxygen concentrator is configured to automatically select whether low pressure oxygen or high pressure oxygen should be output to the user based on the type of connector used to couple a delivery device thereto, or based on characteristics of the delivery device itself.

The invention claimed is: 
     
       1. A system for delivering oxygen to a user, the system comprising:
 an oxygen concentrator that includes:
 a first pump configured to pump atmospheric air through a first sieve bed at a first pressure to generate a first quantity of oxygen, 
 a second pump configured to evacuate nitrogen from a second sieve bed at a second pressure, 
 a pressure amplifier configured to pressurize the first quantity of oxygen to a third pressure to produce pressurized oxygen based on a pressure differential between the first pressure and the second pressure, and 
 a product tank coupled to the pressure amplifier and configured to store the pressurized oxygen for delivery to the user; and 
 
 a user connection switch, configured to deliver the pressurized oxygen to the user via a delivery device. 
 
     
     
       2. The system of  claim 1 , wherein the first pump comprises a compressor pump, and the first pressure has a positive value, and wherein the second pump comprises a vacuum pump, and the second pressure has a negative value. 
     
     
       3. The system of  claim 1 , wherein the pressure amplifier includes:
 a first cylinder that includes a first piston; 
 a second cylinder that includes a second piston that is coupled to the first piston; 
 a first valve coupled to the first pump and to a first region of the first cylinder; and 
 a second valve coupled to the second pump and to a second region of the first cylinder. 
 
     
     
       4. The system of  claim 3 , wherein when the first valve is open the first region is subjected to the first pressure, and when the second valve is open the second region is subjected to the second pressure. 
     
     
       5. The system of  claim 4 , wherein the pressure differential between the first pressure and the second pressure exerts a force on the second piston via the first piston, causing the second piston to compress the first quantity of oxygen to the third pressure. 
     
     
       6. The system of  claim 3 , wherein the first piston has a first cross-sectional area, the second piston has a second cross-sectional area that is smaller than the first cross-sectional area. 
     
     
       7. The system of  claim 6 , wherein the third pressure is proportional to a ratio between the first cross-sectional area and the second cross-sectional area. 
     
     
       8. The system of  claim 1 , wherein the user connection switch is configured to deliver the pressurized oxygen to the user when a first connector is coupled to the user connection switch that opens a valve between the product tank and the delivery device. 
     
     
       9. The system of  claim 1 , wherein the user connection switch is configured to deliver the pressurized oxygen to the user when a first delivery device is coupled to the user connection switch that induces a backpressure that exceeds a threshold value. 
     
     
       10. The system of  claim 1 , wherein the delivery device comprises a low profile nasal cannula configured to deliver pressurized oxygen to the user having a pressure of at least 15 pounds per square inch gage (psig). 
     
     
       11. The system of  claim 1 , further comprising a low pressure product tank that is coupled to the first sieve bed and to the user connection switch and is configured to store the first quantity of oxygen at a fourth pressure that is less than the third pressure, wherein the user connection switch is configured to select, when connected to a high pressure delivery device that operates at a high pressure, a first oxygen flow path in the oxygen concentrator that connects the product tank to the high pressure delivery device, and to select, when connected to a low pressure delivery device that operates at a low pressure, a second oxygen flow path in the oxygen concentrator that connects the low pressure product tank to the low pressure delivery device. 
     
     
       12. An oxygen concentrator, comprising:
 a first pump configured to pump atmospheric air through a first sieve bed at a first pressure to generate a first quantity of oxygen; 
 a second pump configured to evacuate nitrogen from a second sieve bed at a second pressure; 
 a pressure amplifier configured to pressurize the first quantity of oxygen to a third pressure to produce pressurized oxygen based on a pressure differential between the first pressure and the second pressure; and 
 a product tank coupled to the pressure amplifier and configured to store the pressurized oxygen for delivery to the user. 
 
     
     
       13. The oxygen concentrator of  claim 12 , wherein the first pump comprises a compressor pump, and the first pressure has a positive value, and wherein the second pump comprises a vacuum pump, and the second pressure has a negative value. 
     
     
       14. The oxygen concentrator of  claim 12 , wherein the pressure amplifier includes:
 a first cylinder that includes a first piston; 
 a second cylinder that includes a second piston that is coupled to the first piston; 
 a first valve coupled to the first pump and to a first region of the first cylinder; and 
 a second valve coupled to the second pump and to a second region of the first cylinder. 
 
     
     
       15. The oxygen concentrator of  claim 14 , wherein when the first valve is open the first region is subjected to the first pressure, and when the second valve is open the second region is subjected to the second pressure, and wherein the pressure differential between the first pressure and the second pressure exerts a force on the second piston via the first piston, causing the second piston to compress the first quantity of oxygen to the third pressure. 
     
     
       16. The oxygen concentrator of  claim 15 , wherein when the first valve is closed and the second valve is closed, the first region and the second region are subjected to equal pressure, and the pressurized oxygen exerts a counterforce on the first piston via the second piston, causing the first piston to return to a first mechanical limit. 
     
     
       17. The oxygen concentrator of  claim 15 , wherein when the first valve is closed and the second valve is closed, the pressurized oxygen exerts a counterforce on the first piston via the second piston, causing the first piston to return to a first mechanical limit. 
     
     
       18. The oxygen concentrator of  claim 14 , wherein the first piston has a first cross-sectional area, the second piston has a second cross-sectional area that is smaller than the first cross-sectional area, and wherein the third pressure is proportional to a ratio between the first cross-sectional area and the second cross-sectional area. 
     
     
       19. The oxygen concentrator of  claim 12 , further comprising a user connection switch that is configured to deliver the pressurized oxygen to the user via a delivery device when a first connector is coupled to the user connection switch that opens a valve between the product tank and the delivery device. 
     
     
       20. The oxygen concentrator of  claim 19 , wherein the user connection switch is configured to deliver the pressurized oxygen to the user when a first delivery device is coupled to the user connection switch that induces a backpressure that exceeds a threshold value. 
     
     
       21. The oxygen concentrator of  claim 19 , wherein the delivery device comprises a low profile nasal cannula configured to deliver pressurized oxygen to the user having a pressure of at least 15 pounds per square inch gage (psig). 
     
     
       22. The oxygen concentrator of  claim 12 , further comprising:
 a user connection switch configured to deliver the pressurized oxygen to the user via a delivery device; and 
 a low pressure product tank that is coupled to the first sieve bed and to the user connection switch and is configured to store the first quantity of oxygen at a fourth pressure that is less than the third pressure, 
 wherein the user connection switch is configured to select, when connected to a high pressure delivery device that operates at a high pressure, a first oxygen flow path in the oxygen concentrator that connects the product tank to the high pressure delivery device, and to select, when connected to a low pressure delivery device that operates at a low pressure, a second oxygen flow path in the oxygen concentrator that connects the low pressure product tank to the low pressure delivery device. 
 
     
     
       23. A method for compressing oxygen, the method comprising:
 pumping atmospheric air with a first pump through a first sieve bed at a first pressure to generate a first quantity of oxygen; 
 evacuating nitrogen with a second pump from a second sieve bed at a second pressure; 
 pressurizing the first quantity of oxygen to a third pressure to produce pressurized oxygen based on a pressure differential between the first pressure and the second pressure; and 
 storing the pressurized oxygen for delivery to a user.